12V lights in 2010 blue Ridge 5V dimming/brightening

[gat75]

Just completed a search in this forum on why our lights just started dimming & then getting bright. Could not find a "smoking gun."

Keep this RV under a cover year round at lake, (when not taking a vacation trip). It stays plugged in year round also.

Upon arrival this evening, we noticed large scale dimming/brightening of the 12V lights.

Power Pedestal has 124 volts on fluke tester. All recpts have 124V likewise. AC runs OK with no noticeable surge.

I tested all the 12V lugs individually inside the panel, getting 12.8 Volt to all lugs.

Interstate battery installed when I purchased RV in July 2011 has range of 12.7 to 12.2 Volts, bingo thought the battery was issue.

Installed deep cycle boat battery that tested continuous 12.8 Volts. Still having same issues.

It is almost like I am not getting a good ground. What is weird is that we have never had a moments issue with the lights before.

Anybody have a suggestion on another test that I have missed?

Thanks in advance four your help!

[N4VNI]

Converter is failing. Same symptoms as ours. I replaced ours but I was able to repair the old one. Bad solder joint on the circuit board.

[remdog_1]

Check the 120V side, use A/C or microwave. If they work its the converter not keeping the 12v side charged. I had same issue last year. What is the age of your 12v Battery, make sure it has proper water in cells. Black or dark looking cells is not good.

[christopherglen]

Unplug AC power, it he dimming continues, it is not the converter, if it stops, like Old-Biscut said, the converter is on its way out.

[Old-Biscuit]

Your 'converter' is failing........12V lights dimming/getting brighter is classic sign

With 120V AC power to converter the DC output should be steady 13.2V with battery disconnected